Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jesse/openvswitch

Jesse Gross says:

====================
[GIT net-next] Open vSwitch

Open vSwitch changes for net-next/3.14. Highlights are:
* Performance improvements in the mechanism to get packets to userspace
using memory mapped netlink and skb zero copy where appropriate.
* Per-cpu flow stats in situations where flows are likely to be shared
across CPUs. Standard flow stats are used in other situations to save
memory and allocation time.
* A handful of code cleanups and rationalization.
====================

Signed-off-by: David S. Miller <[e-mail]>

include/linux/skbuff.h

···
 		    struct pipe_inode_info *pipe, unsigned int len,
 		    unsigned int flags);
 void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
+unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
+void skb_zerocopy(struct sk_buff *to, const struct sk_buff *from,
+		  int len, int hlen);
 void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len);
 int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen);
 void skb_scrub_packet(struct sk_buff *skb, bool xnet);

include/net/genetlink.h

···
  * @attrs: netlink attributes
  * @_net: network namespace
  * @user_ptr: user pointers
+ * @dst_sk: destination socket
  */
 struct genl_info {
 	u32			snd_seq;
···
 	struct net *		_net;
 #endif
 	void *			user_ptr[2];
+	struct sock *		dst_sk;
 };
 
 static inline struct net *genl_info_net(struct genl_info *info)
···
 		 struct sk_buff *skb, struct net *net, u32 portid,
 		 u32 group, struct nlmsghdr *nlh, gfp_t flags);
 
+struct sk_buff *genlmsg_new_unicast(size_t payload, struct genl_info *info,
+				    gfp_t flags);
 void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
 		  struct genl_family *family, int flags, u8 cmd);
 

include/uapi/linux/openvswitch.h

···
 
 #define OVS_DATAPATH_FAMILY  "ovs_datapath"
 #define OVS_DATAPATH_MCGROUP "ovs_datapath"
-#define OVS_DATAPATH_VERSION 0x1
+
+/* V2:
+ *   - API users are expected to provide OVS_DP_ATTR_USER_FEATURES
+ *     when creating the datapath.
+ */
+#define OVS_DATAPATH_VERSION 2
+
+/* First OVS datapath version to support features */
+#define OVS_DP_VER_FEATURES 2
 
 enum ovs_datapath_cmd {
 	OVS_DP_CMD_UNSPEC,
···
 	OVS_DP_ATTR_UPCALL_PID,		/* Netlink PID to receive upcalls */
 	OVS_DP_ATTR_STATS,		/* struct ovs_dp_stats */
 	OVS_DP_ATTR_MEGAFLOW_STATS,	/* struct ovs_dp_megaflow_stats */
+	OVS_DP_ATTR_USER_FEATURES,	/* OVS_DP_F_*  */
 	__OVS_DP_ATTR_MAX
 };
 
···
 	__u64   rx_dropped;		/* no space in linux buffers    */
 	__u64   tx_dropped;		/* no space available in linux  */
 };
+
+/* Allow last Netlink attribute to be unaligned */
+#define OVS_DP_F_UNALIGNED	(1 << 0)
 
 /* Fixed logical ports. */
 #define OVSP_LOCAL      ((__u32)0)

net/core/skbuff.c

···
 }
 EXPORT_SYMBOL(skb_copy_and_csum_bits);
 
+ /**
+ *	skb_zerocopy_headlen - Calculate headroom needed for skb_zerocopy()
+ *	@from: source buffer
+ *
+ *	Calculates the amount of linear headroom needed in the 'to' skb passed
+ *	into skb_zerocopy().
+ */
+unsigned int
+skb_zerocopy_headlen(const struct sk_buff *from)
+{
+	unsigned int hlen = 0;
+
+	if (!from->head_frag ||
+	    skb_headlen(from) < L1_CACHE_BYTES ||
+	    skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS)
+		hlen = skb_headlen(from);
+
+	if (skb_has_frag_list(from))
+		hlen = from->len;
+
+	return hlen;
+}
+EXPORT_SYMBOL_GPL(skb_zerocopy_headlen);
+
+/**
+ *	skb_zerocopy - Zero copy skb to skb
+ *	@to: destination buffer
+ *	@source: source buffer
+ *	@len: number of bytes to copy from source buffer
+ *	@hlen: size of linear headroom in destination buffer
+ *
+ *	Copies up to `len` bytes from `from` to `to` by creating references
+ *	to the frags in the source buffer.
+ *
+ *	The `hlen` as calculated by skb_zerocopy_headlen() specifies the
+ *	headroom in the `to` buffer.
+ */
+void
+skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen)
+{
+	int i, j = 0;
+	int plen = 0; /* length of skb->head fragment */
+	struct page *page;
+	unsigned int offset;
+
+	BUG_ON(!from->head_frag && !hlen);
+
+	/* dont bother with small payloads */
+	if (len <= skb_tailroom(to)) {
+		skb_copy_bits(from, 0, skb_put(to, len), len);
+		return;
+	}
+
+	if (hlen) {
+		skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
+		len -= hlen;
+	} else {
+		plen = min_t(int, skb_headlen(from), len);
+		if (plen) {
+			page = virt_to_head_page(from->head);
+			offset = from->data - (unsigned char *)page_address(page);
+			__skb_fill_page_desc(to, 0, page, offset, plen);
+			get_page(page);
+			j = 1;
+			len -= plen;
+		}
+	}
+
+	to->truesize += len + plen;
+	to->len += len + plen;
+	to->data_len += len + plen;
+
+	for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
+		if (!len)
+			break;
+		skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i];
+		skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len);
+		len -= skb_shinfo(to)->frags[j].size;
+		skb_frag_ref(to, j);
+		j++;
+	}
+	skb_shinfo(to)->nr_frags = j;
+}
+EXPORT_SYMBOL_GPL(skb_zerocopy);
+
 void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to)
 {
 	__wsum csum;

net/netfilter/nfnetlink_queue_core.c

···
 	spin_unlock_bh(&queue->lock);
 }
 
-static void
-nfqnl_zcopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen)
-{
-	int i, j = 0;
-	int plen = 0; /* length of skb->head fragment */
-	struct page *page;
-	unsigned int offset;
-
-	/* dont bother with small payloads */
-	if (len <= skb_tailroom(to)) {
-		skb_copy_bits(from, 0, skb_put(to, len), len);
-		return;
-	}
-
-	if (hlen) {
-		skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
-		len -= hlen;
-	} else {
-		plen = min_t(int, skb_headlen(from), len);
-		if (plen) {
-			page = virt_to_head_page(from->head);
-			offset = from->data - (unsigned char *)page_address(page);
-			__skb_fill_page_desc(to, 0, page, offset, plen);
-			get_page(page);
-			j = 1;
-			len -= plen;
-		}
-	}
-
-	to->truesize += len + plen;
-	to->len += len + plen;
-	to->data_len += len + plen;
-
-	for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
-		if (!len)
-			break;
-		skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i];
-		skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len);
-		len -= skb_shinfo(to)->frags[j].size;
-		skb_frag_ref(to, j);
-		j++;
-	}
-	skb_shinfo(to)->nr_frags = j;
-}
-
 static int
 nfqnl_put_packet_info(struct sk_buff *nlskb, struct sk_buff *packet,
 		      bool csum_verify)
···
 {
 	size_t size;
 	size_t data_len = 0, cap_len = 0;
-	int hlen = 0;
+	unsigned int hlen = 0;
 	struct sk_buff *skb;
 	struct nlattr *nla;
 	struct nfqnl_msg_packet_hdr *pmsg;
···
 		if (data_len > entskb->len)
 			data_len = entskb->len;
 
-		if (!entskb->head_frag ||
-		    skb_headlen(entskb) < L1_CACHE_BYTES ||
-		    skb_shinfo(entskb)->nr_frags >= MAX_SKB_FRAGS)
-			hlen = skb_headlen(entskb);
-
-		if (skb_has_frag_list(entskb))
-			hlen = entskb->len;
-		hlen = min_t(int, data_len, hlen);
+		hlen = skb_zerocopy_headlen(entskb);
+		hlen = min_t(unsigned int, hlen, data_len);
 		size += sizeof(struct nlattr) + hlen;
 		cap_len = entskb->len;
 		break;
···
 		nla->nla_type = NFQA_PAYLOAD;
 		nla->nla_len = nla_attr_size(data_len);
 
-		nfqnl_zcopy(skb, entskb, data_len, hlen);
+		skb_zerocopy(skb, entskb, data_len, hlen);
 	}
 
 	nlh->nlmsg_len = skb->len;

net/netlink/af_netlink.c

···
 	if (ring->pg_vec == NULL)
 		goto out_put;
 
+	if (ring->frame_size - NL_MMAP_HDRLEN < size)
+		goto out_put;
+
 	skb = alloc_skb_head(gfp_mask);
 	if (skb == NULL)
 		goto err1;
···
 	if (ring->pg_vec == NULL)
 		goto out_free;
 
+	/* check again under lock */
 	maxlen = ring->frame_size - NL_MMAP_HDRLEN;
 	if (maxlen < size)
 		goto out_free;

net/netlink/genetlink.c

···
 EXPORT_SYMBOL(genl_unregister_family);
 
 /**
+ * genlmsg_new_unicast - Allocate generic netlink message for unicast
+ * @payload: size of the message payload
+ * @info: information on destination
+ * @flags: the type of memory to allocate
+ *
+ * Allocates a new sk_buff large enough to cover the specified payload
+ * plus required Netlink headers. Will check receiving socket for
+ * memory mapped i/o capability and use it if enabled. Will fall back
+ * to non-mapped skb if message size exceeds the frame size of the ring.
+ */
+struct sk_buff *genlmsg_new_unicast(size_t payload, struct genl_info *info,
+				    gfp_t flags)
+{
+	size_t len = nlmsg_total_size(genlmsg_total_size(payload));
+
+	return netlink_alloc_skb(info->dst_sk, len, info->snd_portid, flags);
+}
+EXPORT_SYMBOL_GPL(genlmsg_new_unicast);
+
+/**
  * genlmsg_put - Add generic netlink header to netlink message
  * @skb: socket buffer holding the message
  * @portid: netlink portid the message is addressed to
···
 	info.genlhdr = nlmsg_data(nlh);
 	info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
 	info.attrs = attrbuf;
+	info.dst_sk = skb->sk;
 	genl_info_net_set(&info, net);
 	memset(&info.user_ptr, 0, sizeof(info.user_ptr));
 

net/openvswitch/datapath.c

···
 #endif
 
 static struct vport *new_vport(const struct vport_parms *);
-static int queue_gso_packets(struct net *, int dp_ifindex, struct sk_buff *,
+static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
 			     const struct dp_upcall_info *);
-static int queue_userspace_packet(struct net *, int dp_ifindex,
-				  struct sk_buff *,
+static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
 				  const struct dp_upcall_info *);
 
 /* Must be called with rcu_read_lock or ovs_mutex. */
···
 }
 
 /* Must be called with rcu_read_lock or ovs_mutex. */
-const char *ovs_dp_name(const struct datapath *dp)
+static const char *ovs_dp_name(const struct datapath *dp)
 {
 	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
 	return vport->ops->get_name(vport);
···
 	}
 
 	/* Look up flow. */
-	flow = ovs_flow_tbl_lookup(&dp->table, &key, &n_mask_hit);
+	flow = ovs_flow_tbl_lookup_stats(&dp->table, &key, &n_mask_hit);
 	if (unlikely(!flow)) {
 		struct dp_upcall_info upcall;
 
···
 	OVS_CB(skb)->flow = flow;
 	OVS_CB(skb)->pkt_key = &key;
 
-	stats_counter = &stats->n_hit;
-	ovs_flow_used(OVS_CB(skb)->flow, skb);
+	ovs_flow_stats_update(OVS_CB(skb)->flow, skb);
 	ovs_execute_actions(dp, skb);
+	stats_counter = &stats->n_hit;
 
 out:
 	/* Update datapath statistics. */
···
 		  const struct dp_upcall_info *upcall_info)
 {
 	struct dp_stats_percpu *stats;
-	int dp_ifindex;
 	int err;
 
 	if (upcall_info->portid == 0) {
···
 		goto err;
 	}
 
-	dp_ifindex = get_dpifindex(dp);
-	if (!dp_ifindex) {
-		err = -ENODEV;
-		goto err;
-	}
-
 	if (!skb_is_gso(skb))
-		err = queue_userspace_packet(ovs_dp_get_net(dp), dp_ifindex, skb, upcall_info);
+		err = queue_userspace_packet(dp, skb, upcall_info);
 	else
-		err = queue_gso_packets(ovs_dp_get_net(dp), dp_ifindex, skb, upcall_info);
+		err = queue_gso_packets(dp, skb, upcall_info);
 	if (err)
 		goto err;
 
···
 	return err;
 }
 
-static int queue_gso_packets(struct net *net, int dp_ifindex,
-			     struct sk_buff *skb,
+static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
 			     const struct dp_upcall_info *upcall_info)
 {
 	unsigned short gso_type = skb_shinfo(skb)->gso_type;
···
 	struct sk_buff *segs, *nskb;
 	int err;
 
-	segs = __skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM, false);
+	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
 	if (IS_ERR(segs))
 		return PTR_ERR(segs);
 
 	/* Queue all of the segments. */
 	skb = segs;
 	do {
-		err = queue_userspace_packet(net, dp_ifindex, skb, upcall_info);
+		err = queue_userspace_packet(dp, skb, upcall_info);
 		if (err)
 			break;
 
···
 		+ nla_total_size(28); /* OVS_KEY_ATTR_ND */
 }
 
-static size_t upcall_msg_size(const struct sk_buff *skb,
-			      const struct nlattr *userdata)
+static size_t upcall_msg_size(const struct nlattr *userdata,
+			      unsigned int hdrlen)
 {
 	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
-		+ nla_total_size(skb->len) /* OVS_PACKET_ATTR_PACKET */
+		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
 		+ nla_total_size(key_attr_size()); /* OVS_PACKET_ATTR_KEY */
 
 	/* OVS_PACKET_ATTR_USERDATA */
···
 	return size;
 }
 
-static int queue_userspace_packet(struct net *net, int dp_ifindex,
-				  struct sk_buff *skb,
+static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 				  const struct dp_upcall_info *upcall_info)
 {
 	struct ovs_header *upcall;
 	struct sk_buff *nskb = NULL;
 	struct sk_buff *user_skb; /* to be queued to userspace */
 	struct nlattr *nla;
-	int err;
+	struct genl_info info = {
+		.dst_sk = ovs_dp_get_net(dp)->genl_sock,
+		.snd_portid = upcall_info->portid,
+	};
+	size_t len;
+	unsigned int hlen;
+	int err, dp_ifindex;
+
+	dp_ifindex = get_dpifindex(dp);
+	if (!dp_ifindex)
+		return -ENODEV;
 
 	if (vlan_tx_tag_present(skb)) {
 		nskb = skb_clone(skb, GFP_ATOMIC);
···
 		goto out;
 	}
 
-	user_skb = genlmsg_new(upcall_msg_size(skb, upcall_info->userdata), GFP_ATOMIC);
+	/* Complete checksum if needed */
+	if (skb->ip_summed == CHECKSUM_PARTIAL &&
+	    (err = skb_checksum_help(skb)))
+		goto out;
+
+	/* Older versions of OVS user space enforce alignment of the last
+	 * Netlink attribute to NLA_ALIGNTO which would require extensive
+	 * padding logic. Only perform zerocopy if padding is not required.
+	 */
+	if (dp->user_features & OVS_DP_F_UNALIGNED)
+		hlen = skb_zerocopy_headlen(skb);
+	else
+		hlen = skb->len;
+
+	len = upcall_msg_size(upcall_info->userdata, hlen);
+	user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
 	if (!user_skb) {
 		err = -ENOMEM;
 		goto out;
···
 			  nla_len(upcall_info->userdata),
 			  nla_data(upcall_info->userdata));
 
-	nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len);
+	/* Only reserve room for attribute header, packet data is added
+	 * in skb_zerocopy() */
+	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
+		err = -ENOBUFS;
+		goto out;
+	}
+	nla->nla_len = nla_attr_size(skb->len);
 
-	skb_copy_and_csum_dev(skb, nla_data(nla));
+	skb_zerocopy(user_skb, skb, skb->len, hlen);
 
-	genlmsg_end(user_skb, upcall);
-	err = genlmsg_unicast(net, user_skb, upcall_info->portid);
+	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
 
+	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
 out:
 	kfree_skb(nskb);
 	return err;
-}
-
-static void clear_stats(struct sw_flow *flow)
-{
-	flow->used = 0;
-	flow->tcp_flags = 0;
-	flow->packet_count = 0;
-	flow->byte_count = 0;
 }
 
 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
···
 		packet->protocol = htons(ETH_P_802_2);
 
 	/* Build an sw_flow for sending this packet. */
-	flow = ovs_flow_alloc();
+	flow = ovs_flow_alloc(false);
 	err = PTR_ERR(flow);
 	if (IS_ERR(flow))
 		goto err_kfree_skb;
···
 	const int skb_orig_len = skb->len;
 	struct nlattr *start;
 	struct ovs_flow_stats stats;
+	__be16 tcp_flags;
+	unsigned long used;
 	struct ovs_header *ovs_header;
 	struct nlattr *nla;
-	unsigned long used;
-	u8 tcp_flags;
 	int err;
 
 	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
···
 
 	nla_nest_end(skb, nla);
 
-	spin_lock_bh(&flow->lock);
-	used = flow->used;
-	stats.n_packets = flow->packet_count;
-	stats.n_bytes = flow->byte_count;
-	tcp_flags = (u8)ntohs(flow->tcp_flags);
-	spin_unlock_bh(&flow->lock);
-
+	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
 	if (used &&
 	    nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
 		goto nla_put_failure;
 
 	if (stats.n_packets &&
-	    nla_put(skb, OVS_FLOW_ATTR_STATS,
-		    sizeof(struct ovs_flow_stats), &stats))
+	    nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
 		goto nla_put_failure;
 
-	if (tcp_flags &&
-	    nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags))
+	if ((u8)ntohs(tcp_flags) &&
+	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
 		goto nla_put_failure;
 
 	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
···
 	if (start) {
 		const struct sw_flow_actions *sf_acts;
 
-		sf_acts = rcu_dereference_check(flow->sf_acts,
-						lockdep_ovsl_is_held());
+		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
 
 		err = ovs_nla_put_actions(sf_acts->actions,
 					  sf_acts->actions_len, skb);
···
 	return err;
 }
 
-static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow)
+static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow,
+					       struct genl_info *info)
 {
-	const struct sw_flow_actions *sf_acts;
+	size_t len;
 
-	sf_acts = ovsl_dereference(flow->sf_acts);
+	len = ovs_flow_cmd_msg_size(ovsl_dereference(flow->sf_acts));
 
-	return genlmsg_new(ovs_flow_cmd_msg_size(sf_acts), GFP_KERNEL);
+	return genlmsg_new_unicast(len, info, GFP_KERNEL);
 }
 
 static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
 					       struct datapath *dp,
-					       u32 portid, u32 seq, u8 cmd)
+					       struct genl_info *info,
+					       u8 cmd)
 {
 	struct sk_buff *skb;
 	int retval;
 
-	skb = ovs_flow_cmd_alloc_info(flow);
+	skb = ovs_flow_cmd_alloc_info(flow, info);
 	if (!skb)
 		return ERR_PTR(-ENOMEM);
 
-	retval = ovs_flow_cmd_fill_info(flow, dp, skb, portid, seq, 0, cmd);
+	retval = ovs_flow_cmd_fill_info(flow, dp, skb, info->snd_portid,
+					info->snd_seq, 0, cmd);
 	BUG_ON(retval < 0);
 	return skb;
-}
-
-static struct sw_flow *__ovs_flow_tbl_lookup(struct flow_table *tbl,
-					      const struct sw_flow_key *key)
-{
-	u32 __always_unused n_mask_hit;
-
-	return ovs_flow_tbl_lookup(tbl, key, &n_mask_hit);
 }
 
 static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
···
 	struct datapath *dp;
 	struct sw_flow_actions *acts = NULL;
 	struct sw_flow_match match;
+	bool exact_5tuple;
 	int error;
 
 	/* Extract key. */
···
 		goto error;
 
 	ovs_match_init(&match, &key, &mask);
-	error = ovs_nla_get_match(&match,
+	error = ovs_nla_get_match(&match, &exact_5tuple,
 				  a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
 	if (error)
 		goto error;
···
 		goto err_unlock_ovs;
 
 	/* Check if this is a duplicate flow */
-	flow = __ovs_flow_tbl_lookup(&dp->table, &key);
+	flow = ovs_flow_tbl_lookup(&dp->table, &key);
 	if (!flow) {
 		/* Bail out if we're not allowed to create a new flow. */
 		error = -ENOENT;
···
 			goto err_unlock_ovs;
 
 		/* Allocate flow. */
-		flow = ovs_flow_alloc();
+		flow = ovs_flow_alloc(!exact_5tuple);
 		if (IS_ERR(flow)) {
 			error = PTR_ERR(flow);
 			goto err_unlock_ovs;
 		}
-		clear_stats(flow);
 
 		flow->key = masked_key;
 		flow->unmasked_key = key;
···
 			goto err_flow_free;
 		}
 
-		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-						info->snd_seq, OVS_FLOW_CMD_NEW);
+		reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
 	} else {
 		/* We found a matching flow. */
 		struct sw_flow_actions *old_acts;
···
 		rcu_assign_pointer(flow->sf_acts, acts);
 		ovs_nla_free_flow_actions(old_acts);
 
-		reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-					       info->snd_seq, OVS_FLOW_CMD_NEW);
+		reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
 
 		/* Clear stats. */
-		if (a[OVS_FLOW_ATTR_CLEAR]) {
-			spin_lock_bh(&flow->lock);
-			clear_stats(flow);
-			spin_unlock_bh(&flow->lock);
-		}
+		if (a[OVS_FLOW_ATTR_CLEAR])
+			ovs_flow_stats_clear(flow);
 	}
 	ovs_unlock();
 
···
 	}
 
 	ovs_match_init(&match, &key, NULL);
-	err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
+	err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL);
 	if (err)
 		return err;
 
···
 		goto unlock;
 	}
 
-	flow = __ovs_flow_tbl_lookup(&dp->table, &key);
+	flow = ovs_flow_tbl_lookup(&dp->table, &key);
 	if (!flow || !ovs_flow_cmp_unmasked_key(flow, &match)) {
 		err = -ENOENT;
 		goto unlock;
 	}
 
-	reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-					info->snd_seq, OVS_FLOW_CMD_NEW);
+	reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
 	if (IS_ERR(reply)) {
 		err = PTR_ERR(reply);
 		goto unlock;
···
 	}
 
 	ovs_match_init(&match, &key, NULL);
-	err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
+	err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL);
 	if (err)
 		goto unlock;
 
-	flow = __ovs_flow_tbl_lookup(&dp->table, &key);
+	flow = ovs_flow_tbl_lookup(&dp->table, &key);
 	if (!flow || !ovs_flow_cmp_unmasked_key(flow, &match)) {
 		err = -ENOENT;
 		goto unlock;
 	}
 
-	reply = ovs_flow_cmd_alloc_info(flow);
+	reply = ovs_flow_cmd_alloc_info(flow, info);
 	if (!reply) {
 		err = -ENOMEM;
 		goto unlock;
···
 static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
 	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
 	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
+	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
 };
 
 static struct genl_family dp_datapath_genl_family = {
···
 			&dp_megaflow_stats))
 		goto nla_put_failure;
 
+	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
+		goto nla_put_failure;
+
 	return genlmsg_end(skb, ovs_header);
 
 nla_put_failure:
···
 	return -EMSGSIZE;
 }
 
-static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 portid,
-					     u32 seq, u8 cmd)
+static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp,
+					     struct genl_info *info, u8 cmd)
 {
 	struct sk_buff *skb;
 	int retval;
 
-	skb = genlmsg_new(ovs_dp_cmd_msg_size(), GFP_KERNEL);
+	skb = genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
 	if (!skb)
 		return ERR_PTR(-ENOMEM);
 
-	retval = ovs_dp_cmd_fill_info(dp, skb, portid, seq, 0, cmd);
+	retval = ovs_dp_cmd_fill_info(dp, skb, info->snd_portid, info->snd_seq, 0, cmd);
 	if (retval < 0) {
 		kfree_skb(skb);
 		return ERR_PTR(retval);
···
 		rcu_read_unlock();
 	}
 	return dp ? dp : ERR_PTR(-ENODEV);
+}
+
+static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
+{
+	struct datapath *dp;
+
+	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
+	if (!dp)
+		return;
+
+	WARN(dp->user_features, "Dropping previously announced user features\n");
+	dp->user_features = 0;
+}
+
+static void ovs_dp_change(struct datapath *dp, struct nlattr **a)
+{
+	if (a[OVS_DP_ATTR_USER_FEATURES])
+		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
 }
 
 static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
···
 	parms.port_no = OVSP_LOCAL;
 	parms.upcall_portid = nla_get_u32(a[OVS_DP_ATTR_UPCALL_PID]);
 
+	ovs_dp_change(dp, a);
+
 	vport = new_vport(&parms);
 	if (IS_ERR(vport)) {
 		err = PTR_ERR(vport);
 		if (err == -EBUSY)
 			err = -EEXIST;
 
+		if (err == -EEXIST) {
+			/* An outdated user space instance that does not understand
+			 * the concept of user_features has attempted to create a new
+			 * datapath and is likely to reuse it. Drop all user features.
+			 */
+			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
+				ovs_dp_reset_user_features(skb, info);
+		}
+
 		goto err_destroy_ports_array;
 	}
 
-	reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-				      info->snd_seq, OVS_DP_CMD_NEW);
+	reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
 	err = PTR_ERR(reply);
 	if (IS_ERR(reply))
 		goto err_destroy_local_port;
···
 	if (IS_ERR(dp))
 		goto unlock;
 
-	reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-				      info->snd_seq, OVS_DP_CMD_DEL);
+	reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_DEL);
 	err = PTR_ERR(reply);
 	if (IS_ERR(reply))
 		goto unlock;
···
 	if (IS_ERR(dp))
 		goto unlock;
 
-	reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-				      info->snd_seq, OVS_DP_CMD_NEW);
+	ovs_dp_change(dp, info->attrs);
+
+	reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
 	if (IS_ERR(reply)) {
 		err = PTR_ERR(reply);
 		genl_set_err(&dp_datapath_genl_family, sock_net(skb->sk), 0,
···
 		goto unlock;
 	}
 
-	reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-				      info->snd_seq, OVS_DP_CMD_NEW);
+	reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
 	if (IS_ERR(reply)) {
 		err = PTR_ERR(reply);
 		goto unlock;
···
 	.parallel_ops = true,
 };
 
-struct genl_multicast_group ovs_dp_vport_multicast_group = {
+static struct genl_multicast_group ovs_dp_vport_multicast_group = {
 	.name = OVS_VPORT_MCGROUP
 };
 

net/openvswitch/datapath.h

···
 	/* Network namespace ref. */
 	struct net *net;
 #endif
+
+	u32 user_features;
 };
 
 /**
···
 #define ASSERT_OVSL()		WARN_ON(unlikely(!lockdep_ovsl_is_held()))
 #define ovsl_dereference(p)					\
 	rcu_dereference_protected(p, lockdep_ovsl_is_held())
+#define rcu_dereference_ovsl(p)					\
+	rcu_dereference_check(p, lockdep_ovsl_is_held())
 
 static inline struct net *ovs_dp_get_net(struct datapath *dp)
 {
···
 
 extern struct notifier_block ovs_dp_device_notifier;
 extern struct genl_family dp_vport_genl_family;
-extern struct genl_multicast_group ovs_dp_vport_multicast_group;
 
 void ovs_dp_process_received_packet(struct vport *, struct sk_buff *);
 void ovs_dp_detach_port(struct vport *);
 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
 		  const struct dp_upcall_info *);
 
-const char *ovs_dp_name(const struct datapath *dp);
 struct sk_buff *ovs_vport_cmd_build_info(struct vport *, u32 pid, u32 seq,
 					 u8 cmd);
 

net/openvswitch/flow.c

···
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/sctp.h>
+#include <linux/smp.h>
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/icmp.h>
···
 
 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
 
-void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
+void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb)
 {
+	struct flow_stats *stats;
 	__be16 tcp_flags = 0;
+
+	if (!flow->stats.is_percpu)
+		stats = flow->stats.stat;
+	else
+		stats = this_cpu_ptr(flow->stats.cpu_stats);
 
 	if ((flow->key.eth.type == htons(ETH_P_IP) ||
 	     flow->key.eth.type == htons(ETH_P_IPV6)) &&
···
 		tcp_flags = TCP_FLAGS_BE16(tcp_hdr(skb));
 	}
 
-	spin_lock(&flow->lock);
-	flow->used = jiffies;
-	flow->packet_count++;
-	flow->byte_count += skb->len;
-	flow->tcp_flags |= tcp_flags;
-	spin_unlock(&flow->lock);
+	spin_lock(&stats->lock);
+	stats->used = jiffies;
+	stats->packet_count++;
+	stats->byte_count += skb->len;
+	stats->tcp_flags |= tcp_flags;
+	spin_unlock(&stats->lock);
+}
+
+static void stats_read(struct flow_stats *stats,
+		       struct ovs_flow_stats *ovs_stats,
+		       unsigned long *used, __be16 *tcp_flags)
+{
+	spin_lock(&stats->lock);
+	if (time_after(stats->used, *used))
+		*used = stats->used;
+	*tcp_flags |= stats->tcp_flags;
+	ovs_stats->n_packets += stats->packet_count;
+	ovs_stats->n_bytes += stats->byte_count;
+	spin_unlock(&stats->lock);
+}
+
+void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats,
+			unsigned long *used, __be16 *tcp_flags)
+{
+	int cpu, cur_cpu;
+
+	*used = 0;
+	*tcp_flags = 0;
+	memset(ovs_stats, 0, sizeof(*ovs_stats));
+
+	if (!flow->stats.is_percpu) {
+		stats_read(flow->stats.stat, ovs_stats, used, tcp_flags);
+	} else {
+		cur_cpu = get_cpu();
+		for_each_possible_cpu(cpu) {
+			struct flow_stats *stats;
+
+			if (cpu == cur_cpu)
+				local_bh_disable();
+
+			stats = per_cpu_ptr(flow->stats.cpu_stats, cpu);
+			stats_read(stats, ovs_stats, used, tcp_flags);
+
+			if (cpu == cur_cpu)
+				local_bh_enable();
+		}
+		put_cpu();
+	}
+}
+
+static void stats_reset(struct flow_stats *stats)
+{
+	spin_lock(&stats->lock);
+	stats->used = 0;
+	stats->packet_count = 0;
+	stats->byte_count = 0;
+	stats->tcp_flags = 0;
+	spin_unlock(&stats->lock);
+}
+
+void ovs_flow_stats_clear(struct sw_flow *flow)
+{
+	int cpu, cur_cpu;
+
+	if (!flow->stats.is_percpu) {
+		stats_reset(flow->stats.stat);
+	} else {
+		cur_cpu = get_cpu();
+
+		for_each_possible_cpu(cpu) {
+
+			if (cpu == cur_cpu)
+				local_bh_disable();
+
+			stats_reset(per_cpu_ptr(flow->stats.cpu_stats, cpu));
+
+			if (cpu == cur_cpu)
+				local_bh_enable();
+		}
+		put_cpu();
+	}
 }
 
 static int check_header(struct sk_buff *skb, int len)

net/openvswitch/flow.h

···
 #ifndef FLOW_H
 #define FLOW_H 1
 
+#include <linux/cache.h>
 #include <linux/kernel.h>
 #include <linux/netlink.h>
 #include <linux/openvswitch.h>
···
 } __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
 
 struct sw_flow_key_range {
-	size_t start;
-	size_t end;
+	unsigned short int start;
+	unsigned short int end;
 };
 
 struct sw_flow_mask {
···
 	struct nlattr actions[];
 };
 
+struct flow_stats {
+	u64 packet_count;		/* Number of packets matched. */
+	u64 byte_count;			/* Number of bytes matched. */
+	unsigned long used;		/* Last used time (in jiffies). */
+	spinlock_t lock;		/* Lock for atomic stats update. */
+	__be16 tcp_flags;		/* Union of seen TCP flags. */
+};
+
+struct sw_flow_stats {
+	bool is_percpu;
+	union {
+		struct flow_stats *stat;
+		struct flow_stats __percpu *cpu_stats;
+	};
+};
+
 struct sw_flow {
 	struct rcu_head rcu;
 	struct hlist_node hash_node[2];
···
 	struct sw_flow_key unmasked_key;
 	struct sw_flow_mask *mask;
 	struct sw_flow_actions __rcu *sf_acts;
-
-	spinlock_t lock;	/* Lock for values below. */
-	unsigned long used;	/* Last used time (in jiffies). */
-	u64 packet_count;	/* Number of packets matched. */
-	u64 byte_count;		/* Number of bytes matched. */
-	__be16 tcp_flags;	/* Union of seen TCP flags. */
+	struct sw_flow_stats stats;
 };
 
 struct arp_eth_header {
···
 	unsigned char       ar_tip[4];		/* target IP address        */
 } __packed;
 
-void ovs_flow_used(struct sw_flow *, struct sk_buff *);
+void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb);
+void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *stats,
+			unsigned long *used, __be16 *tcp_flags);
+void ovs_flow_stats_clear(struct sw_flow *flow);
 u64 ovs_flow_used_time(unsigned long flow_jiffies);
 
 int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *);

net/openvswitch/flow_netlink.c

···
 	return true;
 }
 
+static bool is_all_set(const u8 *fp, size_t size)
+{
+	int i;
+
+	if (!fp)
+		return false;
+
+	for (i = 0; i < size; i++)
+		if (fp[i] != 0xff)
+			return false;
+
+	return true;
+}
+
 static int __parse_flow_nlattrs(const struct nlattr *attr,
 				const struct nlattr *a[],
 				u64 *attrsp, bool nz)
···
 	return 0;
 }
 
-static int ovs_key_from_nlattrs(struct sw_flow_match *match,  u64 attrs,
-				const struct nlattr **a, bool is_mask)
+static int ovs_key_from_nlattrs(struct sw_flow_match *match,  bool *exact_5tuple,
+				u64 attrs, const struct nlattr **a,
+				bool is_mask)
 {
 	int err;
 	u64 orig_attrs = attrs;
···
 		SW_FLOW_KEY_PUT(match, eth.type, htons(ETH_P_802_2), is_mask);
 	}
 
+	if (is_mask && exact_5tuple) {
+		if (match->mask->key.eth.type != htons(0xffff))
+			*exact_5tuple = false;
+	}
+
 	if (attrs & (1 << OVS_KEY_ATTR_IPV4)) {
 		const struct ovs_key_ipv4 *ipv4_key;
 
···
 		SW_FLOW_KEY_PUT(match, ipv4.addr.dst,
 				ipv4_key->ipv4_dst, is_mask);
 		attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
+
+		if (is_mask && exact_5tuple && *exact_5tuple) {
+			if (ipv4_key->ipv4_proto != 0xff ||
+			    ipv4_key->ipv4_src != htonl(0xffffffff) ||
+			    ipv4_key->ipv4_dst != htonl(0xffffffff))
+				*exact_5tuple = false;
+		}
 	}
 
 	if (attrs & (1 << OVS_KEY_ATTR_IPV6)) {
···
 				is_mask);
 
 		attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
+
+		if (is_mask && exact_5tuple && *exact_5tuple) {
+			if (ipv6_key->ipv6_proto != 0xff ||
+			    !is_all_set((u8 *)ipv6_key->ipv6_src, sizeof(match->key->ipv6.addr.src)) ||
+			    !is_all_set((u8 *)ipv6_key->ipv6_dst, sizeof(match->key->ipv6.addr.dst)))
+				*exact_5tuple = false;
+		}
 	}
 
 	if (attrs & (1 << OVS_KEY_ATTR_ARP)) {
···
 					tcp_key->tcp_dst, is_mask);
 		}
 		attrs &= ~(1 << OVS_KEY_ATTR_TCP);
+
+		if (is_mask && exact_5tuple && *exact_5tuple &&
+		    (tcp_key->tcp_src != htons(0xffff) ||
+		     tcp_key->tcp_dst != htons(0xffff)))
+			*exact_5tuple = false;
 	}
 
 	if (attrs & (1 << OVS_KEY_ATTR_TCP_FLAGS)) {
···
 					udp_key->udp_dst, is_mask);
 		}
 		attrs &= ~(1 << OVS_KEY_ATTR_UDP);
+
+		if (is_mask && exact_5tuple && *exact_5tuple &&
+		    (udp_key->udp_src != htons(0xffff) ||
+		     udp_key->udp_dst != htons(0xffff)))
+			*exact_5tuple = false;
 	}
 
 	if (attrs & (1 << OVS_KEY_ATTR_SCTP)) {
···
  * attribute specifies the mask field of the wildcarded flow.
  */
 int ovs_nla_get_match(struct sw_flow_match *match,
+		      bool *exact_5tuple,
 		      const struct nlattr *key,
 		      const struct nlattr *mask)
 {
···
 		}
 	}
 
-	err = ovs_key_from_nlattrs(match, key_attrs, a, false);
+	err = ovs_key_from_nlattrs(match, NULL, key_attrs, a, false);
 	if (err)
 		return err;
+
+	if (exact_5tuple)
+		*exact_5tuple = true;
 
 	if (mask) {
 		err = parse_flow_mask_nlattrs(mask, a, &mask_attrs);
···
 			}
 		}
 
-		err = ovs_key_from_nlattrs(match, mask_attrs, a, true);
+		err = ovs_key_from_nlattrs(match, exact_5tuple, mask_attrs, a, true);
 		if (err)
 			return err;
 	} else {
···
 	return sfa;
 }
 
-/* RCU callback used by ovs_nla_free_flow_actions. */
-static void rcu_free_acts_callback(struct rcu_head *rcu)
-{
-	struct sw_flow_actions *sf_acts = container_of(rcu,
-			struct sw_flow_actions, rcu);
-	kfree(sf_acts);
-}
-
 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
  * The caller must hold rcu_read_lock for this to be sensible. */
 void ovs_nla_free_flow_actions(struct sw_flow_actions *sf_acts)
 {
-	call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
+	kfree_rcu(sf_acts, rcu);
 }
 
 static struct nlattr *reserve_sfa_size(struct sw_flow_actions **sfa,

net/openvswitch/flow_netlink.h

···
 int ovs_nla_get_flow_metadata(struct sw_flow *flow,
 			      const struct nlattr *attr);
 int ovs_nla_get_match(struct sw_flow_match *match,
+		      bool *exact_5tuple,
 		      const struct nlattr *,
 		      const struct nlattr *);
 

net/openvswitch/flow_table.c

···
 #include <net/ipv6.h>
 #include <net/ndisc.h>
 
-#include "datapath.h"
-
 #define TBL_MIN_BUCKETS		1024
 #define REHASH_INTERVAL		(10 * 60 * HZ)
 
···
 		*d++ = *s++ & *m++;
 }
 
-struct sw_flow *ovs_flow_alloc(void)
+struct sw_flow *ovs_flow_alloc(bool percpu_stats)
 {
 	struct sw_flow *flow;
+	int cpu;
 
 	flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 	if (!flow)
 		return ERR_PTR(-ENOMEM);
 
-	spin_lock_init(&flow->lock);
 	flow->sf_acts = NULL;
 	flow->mask = NULL;
 
+	flow->stats.is_percpu = percpu_stats;
+
+	if (!percpu_stats) {
+		flow->stats.stat = kzalloc(sizeof(*flow->stats.stat), GFP_KERNEL);
+		if (!flow->stats.stat)
+			goto err;
+
+		spin_lock_init(&flow->stats.stat->lock);
+	} else {
+		flow->stats.cpu_stats = alloc_percpu(struct flow_stats);
+		if (!flow->stats.cpu_stats)
+			goto err;
+
+		for_each_possible_cpu(cpu) {
+			struct flow_stats *cpu_stats;
+
+			cpu_stats = per_cpu_ptr(flow->stats.cpu_stats, cpu);
+			spin_lock_init(&cpu_stats->lock);
+		}
+	}
 	return flow;
+err:
+	kfree(flow);
+	return ERR_PTR(-ENOMEM);
 }
 
 int ovs_flow_tbl_count(struct flow_table *table)
···
 static void flow_free(struct sw_flow *flow)
 {
 	kfree((struct sf_flow_acts __force *)flow->sf_acts);
+	if (flow->stats.is_percpu)
+		free_percpu(flow->stats.cpu_stats);
+	else
+		kfree(flow->stats.stat);
 	kmem_cache_free(flow_cache, flow);
 }
 
···
 	struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 
 	flow_free(flow);
-}
-
-static void rcu_free_sw_flow_mask_cb(struct rcu_head *rcu)
-{
-	struct sw_flow_mask *mask = container_of(rcu, struct sw_flow_mask, rcu);
-
-	kfree(mask);
 }
 
 static void flow_mask_del_ref(struct sw_flow_mask *mask, bool deferred)
···
 	if (!mask->ref_count) {
 		list_del_rcu(&mask->list);
 		if (deferred)
-			call_rcu(&mask->rcu, rcu_free_sw_flow_mask_cb);
+			kfree_rcu(mask, rcu);
 		else
 			kfree(mask);
 	}
···
 	return NULL;
 }
 
-struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
+struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,
 				    const struct sw_flow_key *key,
 				    u32 *n_mask_hit)
 {
-	struct table_instance *ti = rcu_dereference(tbl->ti);
+	struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);
 	struct sw_flow_mask *mask;
 	struct sw_flow *flow;
 
···
 			return flow;
 	}
 	return NULL;
+}
+
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *tbl,
+				    const struct sw_flow_key *key)
+{
+	u32 __always_unused n_mask_hit;
+
+	return ovs_flow_tbl_lookup_stats(tbl, key, &n_mask_hit);
 }
 
 int ovs_flow_tbl_num_masks(const struct flow_table *table)
···
 	return NULL;
 }
 
-/**
- * add a new mask into the mask list.
- * The caller needs to make sure that 'mask' is not the same
- * as any masks that are already on the list.
- */
+/* Add 'mask' into the mask list, if it is not already there. */
 static int flow_mask_insert(struct flow_table *tbl, struct sw_flow *flow,
 			    struct sw_flow_mask *new)
 {

net/openvswitch/flow_table.h

···
 int ovs_flow_init(void);
 void ovs_flow_exit(void);
 
-struct sw_flow *ovs_flow_alloc(void);
+struct sw_flow *ovs_flow_alloc(bool percpu_stats);
 void ovs_flow_free(struct sw_flow *, bool deferred);
 
 int ovs_flow_tbl_init(struct flow_table *);
···
 int  ovs_flow_tbl_num_masks(const struct flow_table *table);
 struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *table,
 				       u32 *bucket, u32 *idx);
-struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *,
+struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *,
 				    const struct sw_flow_key *,
 				    u32 *n_mask_hit);
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *,
+				    const struct sw_flow_key *);
 
 bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,
 			       struct sw_flow_match *match);

net/openvswitch/vport.c

···
 #include "vport.h"
 #include "vport-internal_dev.h"
 
+static void ovs_vport_record_error(struct vport *,
+				   enum vport_err_type err_type);
+
 /* List of statically compiled vport implementations.  Don't forget to also
  * add yours to the list at the bottom of vport.h. */
 static const struct vport_ops *vport_ops_list[] = {
···
  * If using the vport generic stats layer indicate that an error of the given
  * type has occurred.
  */
-void ovs_vport_record_error(struct vport *vport, enum vport_err_type err_type)
+static void ovs_vport_record_error(struct vport *vport,
+				   enum vport_err_type err_type)
 {
 	spin_lock(&vport->stats_lock);
 

net/openvswitch/vport.h

···
 
 void ovs_vport_receive(struct vport *, struct sk_buff *,
 		       struct ovs_key_ipv4_tunnel *);
-void ovs_vport_record_error(struct vport *, enum vport_err_type err_type);
 
 /* List of statically compiled vport implementations.  Don't forget to also
  * add yours to the list at the top of vport.c. */